Page end signal for typewriters



Oct. 30, 1951 R HULL 1 2,573,023

PAGE END SIGNAL FOR TYPEWRITERS Filed Dec. 12, 1947 3 Shets-Sheet l Oct.30,1951 HULL 2,573,023

- PAGE END SIGNAL FOR TYPEIWRITERS Filed Dec. 12, 1947 s Sheets-Sheet 2J "Mm Mon RICH/7RD Oct. 30, 1951 R. HULL 2,573,023

PAGE END SIGNAL. FOR TYPEWRITERS Filed Dec. 12, 1947 3 Sheets-Sheet 3Wm? MW Patented Oct. 30, 1951 UNITED STATES PATENTV'OFF'ICE 2,573,023PAGE END SIGNAL FOR TYPEWRITERS Richard Hull, Corinth, Miss. ApplicationDecember 12, 1947, Serial No. 791,291

7 Claims. (01. 197189) This invention relates to improvements in pageend signals for typewriters that indicate to the operator when the endor bottom of the sheet is approaching a'certain position in relation tothe junction of the keys and the platen, and relates particularly tosignals which are operated elec trically.

Heretofore devices of this type have been provided with some means suchas an electrical contact or contacts associated with the platen of atypewriter and a second contact, usually on the carriage, which isdesigned to make electrical contact with the first-mentioned contact,but is prevented from doing this by means of the insulating quality ofthe paper in the typewriter as it is moved between the contacts and onthe platen. Consequently, when the end or bottom edge of the paper hasreached a certain point on the platen, and incidentally a point beyondthe point on the platen associated with the electrical contacts, thepaper has passed from between the contacts, thus allowing them to becomeclosed.

A further object of this invention is to provide an improved electricsignal for typewriters which overcomes the above objections, byproviding contacts which normally remain open or separated and are onlymomentarily urged into a closed position by the return action of theroll advance and carriage return mechanism after the paper has beenadvanced.

Another object of this invention is to provide an electric signalcontact which indicates the approach of the end of the paper in atypewriter which only is urged into a closed positionand in contact withthe paper when the paper isstationary on the platen roll and after theadvance of the paper has taken place.

A still further object of this invention is to provide an electricalsignal which indicates the approach of the end of the paper in atypewriter to the operator and which only momentarily closes the circuitof an electric signal after the actuation of the roll advance andcarriage return mechanism but does not have to be disconnected manuallyafter the circuit has been closed, and does not have to be re-set foreach new sheet of paper.

A further object of this invention is to provide an improved signalwhich indicates the approach of the end of the paper in a typewriterwhich is simple, economical to manufacture, and which can be adapted tobe installed upon any standard typewriter.

The invention is illustrated in certain embodiments, in the accompanyingdrawings in which:

Fig. 1 is a rear plan elevational view of one type of a conventionaltypewriter carriage equipped with my improved sheet end signal;

Fig. 2 is a perspective view of the ground contact strip associated withthe platen roll;

Fig. 3 is an end plan elevational view of the typewriter carriageshowing the linkage which.

connects the switch operating mechanism to the platen roll advancemechanism;

Fig. 4 is a cross sectional view taken on the line type of aconventional typewriter carriage equipped with a modified form of myimproved sheet end signal; J Fig. 8 is an end plan elevational view ofthe carriage, shown in Fig. 7; and

Fig. 9 is a cross sectional view of the carriage shown in Fig. 7, takenon the line 9--9 therein."

Referring now to the drawings, wherein for the purpose of illustrationis shown one embodiment of this invention, in Fig. 1, the numeral II]designates generally a typewriter carriage which has a conventionalplaten roll II (shown in Fig. 4), a conventional manual platen roll knobI2, and conventional platen roll advance mechanism desig.-' natedgenerally as I3. Operating the platen roll advance mechanism I3, is abar or slide I4 (shown in Fig. 3), which is actuated by a conventionalplaten roll advance lever (not shown). The platen roll is advanced inthe usual manner by means of a pawl l5, coacting with a ratchet I6,which turns the platen roll, one, two, or three spaces with eachmovement of the bar I4.

The customary paper pan I'I lies below the platen roll II, and operatingthrough holes in the pan I! are pressure rollers I8 and I9. Thetypewriter carriage II] also contains the usual numerous adjusting andtensioning mechanisms, roller bearings, stops, guides, and the like, allof which are conventional on the typewriter and whic need not bedescribed in detail.

In the form of typewriter shown to illustrate this invention, there isprovided directly below the platen roll II, a rod 23 which is carried ateach end by-frame members 2| and 2|.

In order to assemble my improved signal on' the typewriter carriage, ahole 22 is first drilled through the paper pan [1, as shown more clearlyin Figs. 1, 4 and 5. The purpose of drilling this hole in the paper panI1 is to. permit access through the pan of an electrical contact, whichwill be described in detail later.

v A ground electrical contact strip 23 is aflixed by soldering, welding,or the like, between the frame members 2| and 2|, and is located justbelow and closely adjacent to th platen roll II,

as well as between the paper pan I1 and the platen roll I I, as bestshown in Fig. 4. The ground" contact strip 23 being welded or solderedto the frame members 2| and 2|, obviously will be grounded to thetypewriter carriage. This strip 23 becomes one contact of an electricalswitch, and as shown in Figs. 4 and 5, t he strip 23 must of necessity,be located fully over the hole 22 in the paper pan It is to beunderstood that, while I have illushated and shown the ground electricalcontact strip 23 extending the full length. of. the. platen". roll andwelded or soldered in a ground connection to the frame members 2| and2|", that the platen roll itself may be made of 'anelectricallyconductive rubberized material or may be pro- Turning now to the switchoperating mech ovena second guide-bearing 44, and down through guideeyelets 45, 46, 41 and 48, and is attached at its opposite end to aspring 49, which in turn is vided with an electrical. ground band, if sodesired, which in itself will act as a contact and the strip 23 may beomitted. Theelectrical ground contact strip 23 is also shown asextending the full length ofand slightly beyond the platenroll H, inorder to permit freepassage of the paper. aroundthe platen roll andbetweenthe contact strip 23-, and the paper'pan I 1.

Attached to the-supportingbar 20, by any suitable means,.suchas by aclamp-24. is a pivoted contactswitch generally designated as 25. Thiscontact switch 25 is insulated from the support bar 20, by means ofrubberor other suitable-insulation 26, as can best be seen in Fig. 4.The clamp 24 is adjustable and may consist of two arms 21 and- 23, heldtogether by a nut andbolt 29. It has been found desirable touse such anadjustableclamp for the reason that this permits simple, easy assemblyof: the'clamp-onto. the bar 20; andpermits a slidin adjustment of theclamp longitudinall of the bar to take care ofvariations. in structureof different typewriters.

Carried uponthe clampZ l is=aprojecting membet or pivotbar 30. Thisprojecting member 30 maybe formed integrally with the clamp 24, or maybe welded or soldered thereto, as desired Pivotally mountedontheprojection 3Bis aswin inga member or arm- 3|, which is fixedat one end,as by screw threads, on. the projection 30 to sim-- plify theconstruction thereof; However, it-is to beLunderstoodthat the-swingingmember 3|: may be. of any shape. or configuration desired, and may; be.carried: upon the projection 30 in any desiredamanner, so long asitisprovided with-someformof bearing thatwill permit swinging thereof, butwill not. allow the-swinging member: to move laterally appreciably. onthe. projection 30.

' The opposite end of the arm.3.|. is threaded to. receive-a screw 34;.the endof which forms a contact thereon, as shown. in Fig. 6. The.contact member 34 is in. position to: engage the. contact strip 23, asshown inFig..4-.

The swinging arm 3| is provided withv a cam 36 on the under sidethereof, atone end, as best shown; in Fig.6; Amovementi limiting arm 37is also provided. on the: collar 24,.asshown in Fig. 5, and. ispositioned so as to support the arm 3| when in its downward-most.position. The purpose of this movementlimiting arm 31 is to' act as astop or rest for the arm. 3| and to limit its movement in one direction,so that the arm 3| cannot drop below a. certain pointandinterfere withother mechanisms on the carriage. This. arm 3! preferably is made of.somewhat rigidwireand may be adjustedby. bending when the switch 2.5,installed, upon the carriage of." the typewriter.

Thebracket 24 is mounted on thebar 20; so that1 as the. contact 34swings about the: projjectiom30; it. passes into: and through the hole22.. Thisv permits engagement between. the ground-1 contact? 2 an ontactpointsa.

anchored to the'fra'me member 2| by an eyelet 50. The cable passesdirectly beneath but is spaced'from the cam portion 3B of the arm 3|.

Firmly aflixed to the cable 49, is an operating member, such as anenlarged; log 5:! This lug 5| may be made of any material desired butpreferably. should. be of a material which is adapts ed;- to resistWear, and. it. has been: found that lead proves. very satisfactory. The.lug 5| is secured; on. the cable, 46,. intermediate. the ends of the;.cable and adjacent the cam portion 35,. but is located. on the. cable;4.0 in. such. position that when the cableAfl is imitsnormalorimperative position, the lug 5|is entirely onone side of the cam 36, andwhen the. bar: Lt is moved inward or into a. position toactuatetheplatenrolland the;

cable 40 is drawntight, the. 111g 5| is movedto:

the. position shownindotted. lines in Fig.5, which.

is completely on theopposite-side. of thescam 33..

The cable 43 preferably should beer a, material; which is anon-conductorofelectricity, .However, should it be desired to: use a;cable which: is an electrical conductontbglug 5|, must eitherJbe of anon-conductive. material; or. must. be insulated from the cable.

It will bev seen from this explanation and the: drawings, that. the lug5| passes back andzforth and rubs against. the-cam 3,6, in such; mannerthat. the cam is movedin a counter-clockwise direc-- tion, if the arm;3| has not. previously fallen by gravity against the.- stop 3:1, whenthe: lug and; cable are operated or'moved: from left to right (Fig. 1),looking from the; bac of the carriage to the front, otherwisethe-lug; 5|will Wipe over. the cam 36 without. causing further movement thereof,andthe cam 36 is; moved: in. a clockwisedirectionwhenthelugand cable arereturned to their normal positions, This. movement will' cause theswingingmember 3|; to partially. pivot about its axis 30 andlwhichinturn swings the. arm 3| up and down; the-:swit-chbeing open on the downmovement ofrthe arm 3:1 and urged into a closed positiomwhen the: arm 3|is brought upward. It. is; to be-noted that the contact 34 can neverbear against the-paperwhile it is being. turned'bytherplaten-roll.

The assembly of: the swinging member- 3|' and contact 34.is freeswinging. llhatis to say,. it is moved in a clockwise or closed contactposition. by the'lug 5|, andis -returned to an open position after thelug 5| has passed over the cam 33-; by" gravity. It is. to be here.understood that this return; movement. could be accomplished also bymeans of a spring'.

The switch 25- is; connected in any electric circuit. desired; Thecircuit shown in Fig. 4, in schematic diagram is illustrative of asimple formthat has: been found to operate satisfactorily; The: pivot"30': is: connected. to a wire 52, which inturn i'szconnected to one-sideof a signal 53, such asa lamp, bll or buzzer. The other sideof thesignalzisconne'ctedtoza source of electric current; either A'-. C2 or'abattery 54, and the battery turnis grounded" 'at to'the carriage elf-thetypewriter. It will beseenfrom this description that when the contactpoints 23 and 34 are closed, the electric circuit will be closed, andthe signal 53 will be actuated.

- The operation of my improved signal is as follows:

When the operator of a typewriter operates the platen roll advancelever, it strikes the member I4, to urge the pawl I5, into the ratchetI6, to turn the platen roll. This moves the guide roller 42 toward thebackof the carriage, which ,in turn draws the cable 40, over the roller44, thus shortening the same and moves the lug I from its normalposition, as shown in solid lines, to its tension position, as shown indotted linesin Fig. 5,

The lug 5|, moving against the cam 36 in its initial movement from leftto right, as shown in Fig. 1, causes the swinging arm 3| to first movein a counter-clockwise direction until it comes against the stop 31,provided the arm 3| has not previously fallen there by gravity, and inthis position the contact points 34 and 23 are as far apart as possible.This action insures that the movement of the paper 56, in thetypewriter, will not be interfered with by the contact 34. The lug 5|will merely wipe over the cam 36 once it comes against the stop 31.After the paper and platen roll have been advanced fully and arestationary, the operator releases the advance lever, which in turnpermits the member I4 to return to its normal position. This movementpermits the cable 40 to return to its normal position which returns thelug 5I, from the dotted line position to the solid line position, shownin Fig. 5. v

This movement causes the lug 5| to rub against the cam 36 and urges theswinging member 3! in a clockwise direction which in turn causes thecontact point 34 to be raised and urged against the contact 23. If thepaper 56 has not yet reached the end of the sheet, the contacts 34 and23 will be prevented from closing and the electric circuit will not beclosed, but if the end of the paper 56 has passed over the contact 23,there will be nothingwhich will preventthe contacts from closing theelectric circuit. As soon as the lug 5| moves beyond the cam 36,'theweight of the arm 3| and the screw contact 34 again will cause the armto drop to its normal position. This automatically opens the contactpoints and consequently the electric circuit, thereby giving but a flashor momentary energizing of this electric circuit, energizing the bell,lamp, or buzzer.

Thus it will be seen that the improved switch, embodied in my invention,is fully automatic in its operation, inasmuch as the contact points arenever urged into a closed position when the paper or platen roll aremoving andlikewise the contact points 23 and 34 being normally open, therelease of the signal is accomplished simultaneously with the releasingof the operators hand from the lever bar.

1 In the modification of my invention shown in Figs. 7, 8 and 9, thereis also shown the conventional typewriter carriage designated generallyas I0, the platen roll II and the manual platen roll turning knob I2.Associated with the platen roll II, is the customary roll advancemechanism I3, and the bar I4.

.Supporting the ends of the platen roll, is a frame (not shown) similarto the members 2| and 2|, of Figs. 1 and 2, to which is attached the rod20. To the rod 20 are attached a pair of rigid supports 60 and 6|, whichare clamped thereto by screws 62 and 63.2 Carriedonthe ends of thesupports 'an'd 61 is a link bar 64. On the end of the link bar 64,adjacent the central portion of the platen roll, is an arm 65.Insulating means 66 is provided between the arm and the bar 64 whichinsulates the arm 65 from the typewriter carriage. As shown on theopposite end of the arm 65 is a screw contact 61 which is adapted topass through the hole 22 in the paper pan I1, and which contacts withthe elongated grounding strip 23.

On the end of the bar. 64, opposite the arm 65, is a rigid operatinglink 68, which may be connected thereto or formed integral therewith, asdesired. The link 68 is connected tothe bar I4, as best shown in Fig. 8.This connection between the link 68 and the bar I4 may be made in vari-:ous ways for various types of typewriters. How-- ever, in the form shownin this embodiment of my invention, it has been found that this link maybe satisfactorily affixed to the bar I4, by drilling a hole 69 in oneend of the bar and clamp, ing the end of the link 68 theretoby a nut 10.

In the modification shown in Figs. '7, 8and 9, the typewriter roll I I,the carriage I0, and other general parts of a typewriter notspecifically mentioned above are identical to those shown and describedin connection with Figs. 1 to 6. The elongated contact strip 23, and itsmethod of support are identical in both forms of m invention.

The operation of this form of my inventionis quite similar to that shownin Fig. 1, the pri mary diflerence being in the method of operation ofthe switch and contacts.

The switch contact 61 is insulated from the carriage and is connected toa signal system by a wire 1|, extending to a signal, such as a lamp orbuzzer 12, which in turn is connected to a battery 13, and the battery13 is then grounded at 14 to the typewriter.

When the platen advance bar I4 is moved forward, the arm 68 willbecarried in an arc there: with, thus bringing the contact 61 about thepivot of the bar 64, in a counter-clockwise direction. This will movethe contacts 61 and 23 further apart. When the .bar I4 is released andreturned to its normal operative position, the link 68 will bemoved in aclockwise direction which in turn will let the arm 65 and contact 61also move in a clockwise direction; but the bar 64 being clamped to thelimitedly movable bar I4 will be prohibited'from making a completeswing. If proper adjustment is made of the screw '61, in the arm 65,this motion will cause the arm 65 to spring in a clockwise direction,just sufficient momentarily to urge the contact 61 against the elongatedcontact 23.

, As in the preferred embodiment of my invention, if the typewritercontacts 23 and 61, that is to say, if the endof the sheet of paper 56,has not yet reached a predetermined point beyond the contacts 61 and 23,they will be prevented from meeting or closing. However, when the end ofthe sheet of paper 56 passes beyond the contact strip 23, the contacts61 and 23 will close and the signal indicating, that the end of thesheet of paper 56 has reached a certain point, will then be of themachine.

f In both forms of my invention, I have shown:

and illustrated, as a matter of convenience, the signallamp 53, as beingcarried directl upon thetypewriter carriage. However, the signal lamp,desirable, can bemountedon the frame of the paper 56 is between thegiven to the operator bell or buzzer, whichever may be found:

amazes 1' typewriter, or, desired, may be provided with aniextensionandlocated'at any convenient place on :the typists desk andthus-eliminate the weight of the signal device on the carriage. I

If it is found desirable to locate the signal device 253 at some placeother than on the carriage, a conventional pair of roller -or sliding"electrical contacts will be provided on the carriage and the typewriterframe and will make electrical contact between the pivot 30 and thesignal 53, instead .of the wire '52. These contacts will "be -connectedto the pivot 38 and the signal device :53 by any suitableelectricalconnections. I

Furthermore, both forms of my invention, as illustrated, may be alteredand changed to be adapted to various forms and types of typewriterequipment, without departing from the spirit of my invention, andchanges in wiring diagrams, types of cables, and materialof theswitches, contact points, and the like, may be made for differentoperating conditions also without departing from-the spirit of myinvention.

Iclaim: v

1. The combination with a typewriter carriage, a'platen roll on thecarriage, and a platen roll advance mechanism associated with thecarriage and platen roll, of an electric signal adapted to indicate thatthe end-of a sheet of paper carried by the .platen roll and carriage hasreached a certain position, a switch having contacts carried upon saidcarriage, the contacts of said switch being in a normally open position,and means associated with the platen -roll advance mechanism adapted tourge the contacts of said switch into a closed position'iollowing acompleted advance of said platen roll, the contacts of said switch beingprevented from closing until a sheet of paper has reached a certainposition on the platen ro'll.

2. The combination with a typewriter carriage, a platen roll on thecarriage, and platen roll advancing means, of an electric signal,adaptedto indicate the position of the bottom of a sheet of papercarried by the platen roll and carriage, a switch carried by saidcarriage adapted to 81 platen roll, and means to advance said roll,comprising a pair of normally open contacts, said contacts being adaptedto be separated bythe paper in said typewriter at certain positions ofthe paper 011 the platen roll, operating means associated with one ofsaid contacts and operated by the platen roll advancing means :to urgethe contacts closed in timed relation after each completed advance ofthe platen roll, and a signal connected with said contacts. a

-5. A signal for -a typewriter having a carriage, a, platen roll onthe-carriage, and a platen roll advance mechanism associated with thecarriage and platen roll; comprising aswitch connected with anelectrical signaling circuit adapted to be carried by said carriage,said switch having a pivoted contact in an open position under iioperative conditions, means adapted to insulate said contact from thecarriage, a stop for said pivoted contact, a cam on said pivotedcontact, a cable adapted to be operated by'the platen roll advancemechanism in timed relation after each advance of saidplatenroll, meanscarriedby said cable adapted to oo-act with said cam to urge saidpivoted contact into a closed position, and a stationary contact adaptedto be associated with said-platen roll, said stationary contact beingseparated from the pivoted contact by paper in saidtypewriter until thebottom of said paper reaches a predetermined position in relation to theplaten roll.

v -6. A signal for a typewriter havinga carriage, a platen roll on thecarriage, anda platen roll advance mechanism associated with thecarriage and platen roll, comprising a switch connected to an electricsignaling circuit adapted to be carried by said carriage, said switchhaving a pivoted contact in an open positionunder inoperativeconditions, a resilient hinge for said contact, ,a rigid bar afiixed tosaid hinge and adapted to be rotatably supported on said .earriage andmeans to insulate said contact ,from said .bar, arigid link .carried .bysaid bar adapted to be associated with .the platen roll advancemechanism, said pivoted contact being adapted operate said signal, saidswitch having a pivoted contact and an elongatedcontact extendingsubstantially the length of said platen roll and disposed between theplaten roll and a sheet of paper, the contacts of said switch beingnor.- mally open and being adapted to be urged into a closed positionafter the platen roll has been advanced, said contacts being preventedfrom closing until the bottom of the sheet of paper ,has reached acertain position on theplaten roll, and means associated with the platenroll advancing means for urging said pivoted contact to a closedposition after each completed advance of the platen roll.

3. A signal for a typewriter havinga carriage, a platen roll that isadvanced step-by-step to move a sheet of paper in said typewriter, and

means associated with the platenroll for advancingthe same, comprising anormally open pivoted contact, a stationary contact coasting with thefirst-mentioned contact to operate a signal, said contacts being adaptedto {be separated by the paper when in certain positions on "the platenroll, operating means associated with the pivoted contact'and operatedbythe platen roll advancing means, said last mentioned means-being adaptedtooperatein timed relation after each advance of the platen :roll, and asignal connected'with said contacts. 7

A signal switch for a' typewri-ter having a to be operated in timedrelation after each a'd vance of said platen roll, and a stationary,cone, tact adapted to be associated with said platen roll and; separatedfrom the pivoted contaotby paper in said typewriter untilthe bottom of,Said pape r ach s a predet rmined p n in ela tion to :the platen roll.

.h-Asignal device for a typewriter having a platen roll and means toadvance said roll-comprising spaced electrical contacts adapted .to re,ceive sheet of paper therebetween in said type writer, means adapted tomount said contact onthe typewriter for relative movement to'.,, a nf nine position when the paper is i t t po d therebetweenand to -.an engagg sition in the absence of the paper, and ,means operated by the platenroll advancing means following each completed movement of said platenroll ,for causing relative movement of thecontacts to an engagingosition.

. RICHARD REFERENCES CITED UNITED STATES PATENTS Number 7 Name ,Date- "51 As y r--,-----.- NOV. 1.8251 1,223,379 Gardner Apr. 24, 1917

